(a) Field of the Invention
The present invention relates to a liquid crystal display (“LCD”) and method thereof. More particularly, the present invention relates to an LCD that can adjust different voltages of sub-pixels while ensuring an aperture ratio, and a method of improving an aperture ratio of the LCD.
(b) Description of the Related Art
A liquid crystal display (“LCD”) is one of the most widely used flat panel displays. The LCD includes two display panels provided with electric field generating electrodes, such as pixel electrodes and a common electrode, and a liquid crystal layer interposed between the two display panels. In the LCD, voltages are applied to the electric field generating electrodes to generate an electric field in the liquid crystal layer. Due to the generated electric field, liquid crystal molecules of the liquid crystal layer are aligned, and polarization of an incident light is controlled, thereby displaying images.
The LCD also includes switching elements connected to the respective pixel electrodes, and a plurality of signal lines such as gate lines and data lines for controlling the switching elements and applying voltages to the pixel electrodes.
Among these LCDs, a vertical alignment (“VA”) mode LCD, which arranges major axes of liquid crystal molecules so as to be vertical to the display panel in the state where an electric field is not applied, has been widely used due to a high contrast ratio and a wide reference viewing angle. Here, the reference viewing angle implies a viewing angle that is 1:10 in contrast ratio, or a critical angle of gray-to-gray luminance reversion.
In order to approximate side visibility to front visibility in the VA mode LCD, a method of causing a difference in transmittance by dividing one pixel into two sub-pixels and applying different voltages to the two sub-pixels has been suggested.
An example of a method includes applying the same voltage to two sub-pixels and dropping the voltage of one sub-pixel by using a separate switching element. Meanwhile, as the size of the LCD increases, the number of signal lines also increases.